Dental pulp stem cells (DPSCs) play an integral role during dentine injury where they migrate towards the injury site, proliferate, differentiate into odontoblast-like\ud cells and secrete a mineralised matrix, protecting the vital pulp tissue and preserving the tooth organ. Dentine matrix proteins (DMP) may have a role in stimulating this\ud reparative dentine formation. Multiple adult stem cells make up the DPSC population. Within this study progenitor\ud cells were isolated from dental pulp by preferential fibronectin adherence (FNA) or using magnetic activated cell sorting (MACS) to isolate P75 expressing neural crest\ud cells. Clonally expanded colonies were established. The proliferative FNA and P75-sorted populations were shown to be distinct progenitors with differing morphology\ud and stem cell marker expression. One FNA clonal population was differentiated into mesenchymal lineages that established it as a multipotent DPSC population.\ud Clonal populations were supplemented with DMP in vitro to examine the potential role of DMP in modulating cell behaviour during dentine injury. Supplementing with\ud DMP had a dose dependent response on DPSC viability, increased cell numbers,reduced apoptosis and promoted cell migration, suggesting that the growth factors in\ud DMP may have a positive synergistic effect on DPSC behaviour. Fluorescently stained DPSCs were microinjected into transverse tooth slices and placed in culture to develop an ex vivo model to study DPSC behaviour in a tooth\ud environment. Injected cells remained viable after 7 days of culture, providing proof of concept data that DPSCs can be localised for study in situ. This thesis was successful in the isolation of clonal populations representing\ud progenitor cells with different characteristics. Supplementing DPSCs with DMP promoted cell behaviour facilitating reparative dentinogenesis, indicating a potential clinical application for DMP in restorative therapy. The study of DPSCs using the ex\ud vivo model will be important in further development of these novel therapies for dental tissue regeneration.

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